Sewing machine specifically adapted for domestic use



March 8, 1949. F. GEGAUF 2,464,079

' SEWING MACHINE SPECIFICALLY ADAPTED FOR DOMESTIC USE 2 Sheets-Sheet 1Filed Feb. 14, 1945 7 4 I I, I I

March 8, 1949.

F. GEGAUF l SEWING MACHINE SPECIFICALLY ADAPTED FOR DOMESTIC USE.

2 Sheets-Sheet 2 Filed Feb. 14, 1945 Patented Mar. 8, 1949 SEWINGMACHINE SPECIFICALLY ADAPTED FOR DOMESTIC USE Fritz Gegauf, Steckborn,Switzerland, assignor to Fritz Gegaufs Siihne Aktiengesellschaft,Steckborn, Switzerland Application February 14, 1945, Serial No. 577,805

In Switzerland April 11, 1944 12 Claims.

This invention relates to sewing machines particularly for domestic useprovided with a freely projecting arm containing the shuttle. Suchsewing machines have been put into use particularly in households forthe reason that they permit of conveniently mending that kind ofstockings which can be pulled over or pushed on the projecting arm ofthe machine, so that the otherwise conventional rolling of the stockingto be mended on a mending ring (darnlng ring) can be done away with. Onthe other hand it is necessary that with such a machine all mechanicalsewing operations likely to arise in households can be carried out sothat it must be possible to work in such machines with very thin andalso very thick thread material and with fabrics from the thinnest up tothe thickest kind.

For this purpose the shuttle mechanism commonly known as a central spoolshuttle has proved to be the most advantageous, due to being the leastsensitive when applied to any of the yarns and fabrics to be employedwith a view to effecting perfect stitching. This shuttle mechanism inwhich the shuttle performs an oscillatory rocking movement of an angularrange of minimum 220 has a certain space requirement in the axialdirection of the shuttle driving member which requirement is furtherincreased by that of the movement transmission means for the fabricmember, which has to be arranged in the immediate vicinity of the drive,and of the mounting means for the shuttle driving member. That type offabric feed member has proved to be the most reliable which operates byperforming rectangular motion.

In order to be able to mend or sew in the sewing machine stockings,sleeves and so forth the openings of which are relatively small thecross sectional contour of the freely projecting arm of the machineincluding the shuttle must remain within corresponding limits. Thedifficulties resulting from this requirement in respect of theconstruction to be chosen, that is, the accommodation of the movableparts previously referred to Within the limited hollow space of theprojecting machine arm are still increased in the event that in such asewing machine the shuttle is to be so arranged that its axis extendstransversely to the longitudinal axis of the projecting arm for thepurpose of providing for the needle bar, apart from reciprocating in thevertical direction, to perform in addition a transversely reciprocatorymovement, thereby to permit of efiecting zigzag stitching.

In the sewing machine according-to the present invention a mountingshaft isarranged which is transversely mounted in the projecting arm andis provided with an overhung part which carries the shuttle drivingmember and a gear which is built into said member, the gear intermeshingwith a rack which causes the shuttle driving member, to performoscillatory rocking movements.

This arrangement results in such a saving in available cross sectionalarea of the projecting arm of the sewing machine that this crosssectional arm area satisfies the requirements of practice referred to inthe opening paragraphs. Consequently the machine can be equipped with acentral spool shuttle and with a fabric feed member operating byperforming rectangular motion and with a device for eifecting zigzagstitching. v

An embodiment of the present invention representing a sewing machineaccording to the same is illustrated by way of example only in theaccompanying drawings in which Fig. 1 shows a longitudinal sectionalelevation of the machine according to the present invention;

Fig. 2 is a plan view of the projecting machine arm with the inner partsthereof exposed;

Fig. 3 shows a longitudinal section of the front end of the projectingmachine arm;

Fig. 4 shows a larger scale cross section of the said projecting armwithin the embrace of the looper driving member;

Fig. 5 is a partial vertical cross sectional view of the machine, and

Figs. 6 and 7 represent partial vertical longitudinal sections of theprojecting arm of the machine.

In the drawings a table board supported sewing machine is depicted whichhas a base plate I for carrying the machine casing 2 which is providedwith an upper cantilever arm 3 and with a lower freely projecting arm 4which is arranged counter position to the former arm and includes thetwo-armed shuttle driving member 5. The latter serves for driving acentral spool shuttle (not shown) relative to which, in the operation ofthe machine, the mounting axle 6 of the shuttle driving member 5performs an oscillatory rocking movement through an angular range ofabout 220 by means of a gear 1 which is built into the shuttle drivingmember 5 in the manner as shown in Fig. 4' and which is in mesh withteeth on the under side of a rack bar 8. The rack bar 8 islongitudinally displaceably arranged in thelongitudinal direction of theprojecting arm 4 by means of a guide 9.

The mounting shaft or axle B, which is transversely arranged in one ofthe side walls of the arm 4, carries by means of an overhung portionthereof the gear 1 and the shuttle driving member 5 which is supportedby a connecting strip between the gear I and a flange 5' on the axle 6.The gear I, the shuttle driving member 5 and the flange 6' are connectedto each other and thus to the axle 6 circumferentially thereof byconnection elements, such as pins 6" or keys, so as to be rigidly unitedwith said shaft. On the front end of the overhung part of the mountingshaft 6 a covering I is detachably connected by means of a screw H!which exerts pressure on the face of the gear I fitted thereto by meansof a conical face, so that the gear 1 and the shuttle driving member arefirmly urged against the stop or bearing surface presented by the flange6' of the axle.

On the removal of the screw III which is sunk in a central depression inthe covering disc ill the parts ID, I and 5 can be dismounted from themounting shaft 5. The diameter of the coverin disc I0 is larger thanthat of the gear I and is situated so close by the rack controlledgearing I, 8 as to protect the latter within its embrace against lateralaccess of thread waste and foreign matter to said gearing. On theshuttle guideway carrier casing II or as hereinafter briefly termed,shuttle guide casing, on the apertured side of said casing adjacent tothe shuttle guideway a protecting ring H is arranged which is forcedagainst the immovable shuttle guide casing by means of a leaf spring 12of a pivotal stirrup l3 and is thus secured in position.

The pivotal stirrup l3 which is mounted on a pivot bolt l4 and isprovided with two upwardly extending shanks has a stop pin l5 connectedto one of said shanks for the purpose of retaining the pivotal stirrup[3 in operative position by cooperation with a spring retaining arm [6.On the pivot bolt I4, which engages in the stationary wall of theprojecting arm 4 of the machine, is further mounted a pivotal cover I!which in the closed position shuts an opening which is arranged in alongitudinal side of the said projecting arm 4 opposite to the mountingaxle 6 and provides for access to the shuttle (not shown) located in theshuttle driving member 5 as well as to the spool.

The pivotal cover I! is retained in closed position by means of a latchl9 which engages under the head of a set screw I8 on said lid (Figs. 1and 2), said latch l9 being maintained in operative position by a coiledspring 20. This latch l9 has a head 2| positioned in a recess which isprovided on the front face of the wall of the said projecting arm 4 sothat by exertion of pressure by a finger of the hand on the head 2| fromwithout the latch I9 can be pivotally displaced so as to release the setscrew l8, whereupon the pivotal lid I1 swings automatically downward byaction of its own weight about th pivot bolt I4 into the chain-dottedopen position as shown in Fig. 4.

Subsequently, by correspondingly forcing back the spring retaining armIS the stop pin 15 provided on the pivotal stirrup l3 can be given freepassage, whereupon the pivotal stirrup l3 swings out from the operativeposition into the position shown in chain-dotted lines in Fig. 4, due torelaxation of the leaf spring 12, and the protecting ring II can bedetached from the shuttle guide casing H, thereby completely to clearthe access 4 to the path of movement of the shuttle, for example, forthe purpose of cleaning the shuttle guideway.

Due to the fact that the rack 8, which serves for moving back and forththe gear 1 of the shuttle driving member 5, meshes with its lower toothsystem in the gear 1, thread waste as well as foreign matter, that mayhave come within the range of the rack controlled gearing can drop outdownwardly. As on the other hand the covering disc [0 practicallyprevents foreign matter from laterally intruding into the rackcontrolled gearing l, 8 the latter is safeguarded against disturbinginfluence by foreign matter. The pivotal stirrup Hi can, if desired, beseparately mounted, by being arranged together with the pivotal cover I!on one and the same pivot bolt. Instead of providing a single curvedleaf spring I2 on the pivotal stirrup l3, several individual springs maybe provided for the purpose of elastically forcing the protecting ringII against the looper guide casing II.

The described mode of arranging and constructing the drive for theshuttle driving member 5 warrants the use of the central spool shuttleand of a fabric feed member performing the usual rectangular movement.In Figs. 2 and 4 the numeral 22 design-ates the fabric feed member whichis mounted on two supporting arms 24 by means of a rockable axle 23 andis moved up and down by a roller carrier lever 21, when the machineoperates. The roller carrier lever 21 which is fixed to a shaft 28 isswung back and forth by a second roller carrier lever 29, which is alsoconnected to the shaft 28, from the topside of a control disc 30. Thecontrol disc 30 is secured to an upstanding shaft 3! and has itsunderside operatively connected by means of a link 32 with the rack 8which has the reciprocatory motion imparted to it in this way, wherebythe gear I and consequently also the shuttle drive member 5 togetherwith it is correspondingly oscillated. The upstanding shaft 3| isrotatively connected at the top by means of a bevel wheel drive 33 withthe driving shaft 34 from which by means of a crank 35 and a link 36 theup and down movement of the needle bar 31 is effected.

The needle bar 3'! is mounted in an upper and a lower guide 38 and 39respectively of a rockable holder 40 which in turn can be rocked bymeans not shown about a vertical shaft if by means of the needle 4| azigzag stitching is to be eifected instead of a normal stitching. Thefabric feed member 22 carries on its topside, advantageously,rectilinear serrations in the same manner as in sewing machines that aredevoid of a projecting arm. The end face of the projecting arm 4 isshaped similar to a darnin ball. In this connection the embossed endface of the projecting arm 4 is situated so close by the needle openingof the throat plate 55 and is so dimensioned as to permit ofconveniently mending stockings even at the tip of their toe portions ifthe stockings are appropriately pulled over the freely projecting arm 4,due to the fact that in said arm the precedingly mentioned parts of theactual sewing mechanism can be accommodated in a relatively small space.

On the driving shaft 34 a cam disc 42 (Figs. 5 and 1) is fastened whichis situated between forked arms of a two-armed lever 43 and swings saidlever back and forth about an axle, that is, a bearing pin 44, when thesewing machine operates, this swinging movement being transmitted fromthe swingable lever 43 to an arm I 45 and thereby to a shaft 46 on whichin addition to said arm 45 are secured the two supporting arms 24carrying the rockable axle 23 of the fabric feed member 22 and formingtogether a self-contained unit as shown in Fig. 3. By this means thefabric feed member 22 is reciprocated transversely of the shaft 49 sothat said member in conjunction with the vertical reciprocatory movementimparted thereto by the roller carrier lever 21 (Figs. 4 and 1) effectsthe rectangular motion required for the appropriate feed of the fabric,that is, the sewing work.

The bearing pin 44 of the swinging lever 43 is arranged on a slide block41 (Figs. 1 and 5) which is situated in a cross groove 48 of a settablebody 49 which carries a bearing stud 59. On the settable body 49 ahandle 5| is fixed which projects out of the machine casin 2 and throughwhich the settable body 49 can be turned in unison with its bearing stud50 to a restricted extent and can thus be accordingly adjusted relativeto a scale which is arranged on an arcuate segment 52. Associated withthe scale is a stationary mark which is arranged on the outside of thecasin 2 at a window 53 through which the adjustment of the settable body49 at the time being is visually exhibited. As will be seen from Fig. 1a hand controllable screw 54 engages in a conical recess in the settablebody 49 and extends with its threaded portion into a screw bore in themachine casing 2. By inserting the point of the hand controllable screw54 into the conical recess in the settable body 49 more or less therange of movement of the swinging lever 43 is more or less restricted.By

this means the length of stitch in the sutures is defined in that by theswingable lever 43 the fabric feed member 22 has reciprocatory movementimparted thereto via the arm 45 and the shaft 46.

To the driving shaft 34 is correlated a belt drive 56 (Fig. 1) which bymeans of a further belt drive 57 is operatively connected with anelectric driving motor (not shown). This driving motor is positionedlaterally of the machine casing on one of the longitudinal sides of thelatter.

I claim:

1. In a sewing machine having an oscillatory shuttle driving member, incombination, a machine base, a freely projecting hollow arm provided onsaid base for Work supporting purposes, a shaft mounted in said arm intransverse relation thereto, said shaft having a portion extending intothe interior of said arm in overhung relation to said interior andcarrying the shuttle driving member, a gear on said driving member, anda rack cooperating with said gear for oscillating said shuttle drivingmember.

2. In a sewing machine particularly for domestic use, in combination, amachine base, a freely projecting hollow arm provided on said base forwork supporting purposes, a mounting shaft mounted in said arm intransverse relation thereto, a shuttle driving member, a gear on saiddriving member, said shaft having a portion extending into the interiorof said arm in overhung relation to said interior and carrying theshuttle driving member, a covering disc detachably arranged on the endface of said overhung shaft portion, a shoulder provided on said shaftportion, said disc tending to urge said gear and said driving member inthe axial direction against said shoulder, and a rack cooperating withsaid gear for oscillating said shuttle driving member.

3. In a sewing machine, in combination, a machine base, a freelyprojecting hollow arm provided on said base for work supportingpurposes, a shuttle driving member, a shaft mounted in said arm intransverse relation thereto and having a portion extending into theinterior of said arm in overhung relation to said interior and carryingthe shuttle driving member, a gear on said driving member, a coveringdisc detachably arranged on the end face of said overhung shaft portion,a conical face carried by said disc, a shoulder provided on said shaftportion, said disc tendin to urge said gear and said driving member inthe axial direction against said shoulder by cooperation of saidconical-face with said gear, and. a rack engaging with said gear foroscillating said shuttle driving member.

4. In a sewing machine, in combination, a machine base, a freelyprojecting hollow arm provided on said base for work supportingpurposes,

' a shuttle driving member, a shaft mounted in said arm in transverserelation thereto and having a portion extendin into the interior of saidarm in overhung relation to said interior and carrying the shuttledriving member, a gear on said driving member, a covering discdetachably arranged on the end face of said overhung shaft portion, aconical face carried by said disc together with a seat for a centralconnecting screw head, a shoulder provided on said shaft portion, saiddisc tendin to urge said gear and said driving member in the axialdirection against said shoulder by cooperation of said conical face withsaid gear, and a rack cooperating with said gear for oscillating saidshuttle driving member.

5. In a sewing machine, in combination, a machine base, a freelyprojecting hollow arm provided on said base for work supportingpurposes, a shuttle driving member, a shaft mounted in said arm intransverse relation thereto and having a portion extending into theinterior of said arm in overhung relation to said interior and carryingthe shuttle driving member, a gear on said driving member, a coveringdisc detachably arranged on the end face of said overhung shaft portion,a shoulder provided on said shaft portion, said disc tending to urgesaid gear and said driving member in the axial direction against saidshoulder, a rack cooperating with said gear for oscillating said shuttledriving member, said rack having teeth on its under side forintermeshing with the top portion of the teeth on said gear, saidcovering disc protecting the rack drive formed by said gear and saidrack against access of foreign matter.

6. In a sewing machine, in combination, a machine base, a freelyprojecting hollow arm provided on said base for work supportingpurposes, a shuttle driving member, a shaft mounted in said arm intransverse relation thereto and having a portion extending into theinterior of said arm in overhung relation to said interior and carryingthe shuttle driving member, a gear on said driving member, a coveringdisc detachably arranged on the end face of said overhung shaft portion,a shoulder provided on said shaft portion, said disc tending to urgesaid gear and said driving member in the axial direction against saidshoulder, connection elements arranged on said shoulder interconnectingsaid gear and said shuttle driving member circumferentially thereof intoa rigid unit, and a rack cooperating with said gear for oscillating saidshuttle driving member.

associated with said. pivotal cover, cover, whenin closed position,resiliently maintains said protecting ring in position of confining saidguideway, and a rack cooperating with said gear for oscillating saidshuttle driving member.

- poses-ashuttle'driving'member, a shaft mounted in said-arm intransverse relation'thereto and having 'a'portion extending into theinterior of said arm in overhung relation to said interior and carryingthe shuttle driving member, a gear on said driving member, -a shoulderfixed to said shaft portion, pin-like connection elements secured tosaidshoulder and arranged to interconnect said gear and said shuttle drivingmem- -ber,'thereby-providi-ng a rigid unit between said gear, saiddriving member and said shaft portion, anda rack cooperating with saidgear for oscillating said shuttle driving member.

8. In as'ewing machine, in combination, a machine base, -a 'freelyprojecting hollow arm provided on said base'for work supportingpurposes, a shuttle driving member, a shaft mounted or in said arm'intransverse relation thereto and having :aportion extending into theinterior of said arm in overhung relation tosaid interior and carryingthe shuttle driving member, a gear on said driving member,-a side of thehollow arm having an aperture opposite to said driving member and saidgear, a pivotal cover arranged in front of 'saidaperture in: said sidewall for giving free access to said driving member through saidaperture; and a rack cooperating with said gear for oscillating saidshuttle driving member.

9. In :a sewing machine, in combination, a

machine base, ia freely projecting hollow arm provided onisaid base forwork supporting ,purposes, a shuttle driving member, an axle mounted insaidarm 'in'transverse relation thereto and having a portion extendinginto the interior of I said arm in overhung relation to said interiorand carrying the shuttle driving member, a gear on Y said drivingmember, a shuttle guidecasing carrying a shuttle guideway forcooperation with said shuttle driving member, said hollow arm having anaperture in one side-wall opposite to said drivi'n'g member :andsaidgear, a protecting ring arranged in'front of "said guideway forconfining -said'guideway adjacent said aperture'd side wall "opposite tosaid aperture remotefrom said axle portion carrying said driving memberand gear, a pivotal cover arranged infront of said aperture in 'said.sidewall for giving free access to said driving memberthroughsaidaperture, spring means so that the 10. In a sewingmachinaincombihation, a

'ma'chinebase, a freely projecting hollow'arm provided on-said baseforwork supporting purposes, ashuttle driving member, a shaft mounted insaid arm in transverse relation thereto and having a portion extendinginto'the interior of said arm in overhung :relation vto said interiorand carryngithe'shu'ttle driving member, a gear onv said driving member,a shuttle guide casing carrying a shuttle guidewayfor coopera'tion'with"saidshuttle drivingmemb'er, a protecting ring confiningsaid-shuttlefguideway on the side of said guideway remote from saidshaft portion carrying said driving member together with said gear,spring means resiliently urging said protecting ring against sad shuttleguide casing,

on said'driving member, a shuttle'guide casing carrying a shuttleguideway'for cooperation with said shuttle driving member, a protectingring confining said shuttle guideway on the side of said guideway remotefrom'said shaft portion carrying said driving member togethertwith saidgear, spring means resiliently urging said protecting ring against saidshuttle guide casing, a pivotal stirruparranged toforce said protectingring against said shuttle guide casing, and a rack cooperating with saidgear for oscillating said shuttle driving member.

12. Ina sewing machine, incombination, a machine base, a freelyprojecting hollow arm provided on said base' for work supporting.purposes, a shuttle driving member, an axle mounted in said arm intransverse relation thereto and having a portion extending into theinterior of said farm in overhung relation to said interior and carryingthe shuttle driving member, a gear on said driving member, a shuttleguide casing carrying a shuttle guideway for cooperation with saidshuttle driving member, a protecting ring confining said shuttleguideway 0n the side of said guideway remote from said axle portioncarryin'gsaid driving member together with said gear, spring meansresiliently urging'said protecting ringaganst said shuttle gude casing,a pivotal stirrup arranged to force said protecting ring against saidshuttle guide casing, a side wall portion on said projecting hollow armhaving an aperture permitting access to said pivotal stirrup,

REFERENCES CITED The following references-are of recordin the fileofthis patent:

UNITED STATES" PATENTS Number Name Date 1,300,843 Kaumeyer et al. Apr,15, 1919 2,325,467 Beyer July 27,1943

